sorry, I solved the problem I edited my yum.conf file and I deleted the string corresponding to the kernel* thanks for everything 2013/10/10 Paolo De Michele <paolo at paolodemichele.it> > this is the ls command in my /etc/yum.repos.d/ directory: > > CentOS-Base.repo CentOS-Debuginfo.repo CentOS-Media.repo > CentOS-Vault.repo epel.repo epel-testing.repo > > which repository I have to enable? > > > 2013/10/10 Reindl Harald <h.reindl at thelounge.net> > >> >> >> Am 10.10.2013 15:09, schrieb Paolo De Michele: >> > if I try: >> > >> > # yum install kernel-headers >> > Loaded plugins: fastestmirror, security >> > Loading mirror speeds from cached hostfile >> > * base: ftp.hosteurope.de >> > * epel: mirror.de.leaseweb.net >> > * extras: ftp.hosteurope.de >> > * updates: ftp.hosteurope.de >> > Setting up Install Process >> > No package kernel-headers available. >> > Error: Nothing to do >> > >> > why? >> >> because you most likely excluded it somewhere >> in /etc/yum.repos.d/ or /etc/yum.conf >> >> >> >